Now, to the trial of whitey bulger and the mysterious and suspicious death of a potential witness. His body turned up by the side of the road. And we could know later today how he died. Ron claiborne has the story. Reporter: The mystery continues to swirl. How did stephen rakes die? Increasingly, it appears that rakes, who was to testify against former mob boss james "whitey" bulger may have been killed, not a suicide as first thought. Given the timing happening as it did here, in the midst of the trial. Reporter: Rakes' body was found a week ago, in a boston suburb, far from his home. No wallet. No i.D. His car missing. But he had no signs of trauma. And an autopsy was inconclusive. Investigators say it appears his body was dumped where it was found. And are calling his death suspicious. Rakes is expected to testify how he says bulger extorted him into selling his south boston liquor store 30 years ago. But last week, prosecutors decided not to call rakes to the stand. At the bulger trial tuesday, more fireworks. He key prosecution witness admitted stephen flemmi came under intense krcross-examination, that he personally saw bulger kill several people, inqudding debor debor deborah hussey. The prosecution is expected to rest by the end of this week. For "good morning america," ron claiborne, abc news, new york.

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James 'Whitey' Bulger Witness Found Dead

New details emerge in the trial of infamous Boston mob boss.

Bulger Witness' Friends Say Suicide 'Impossible'

Stephen Rakes, a prosecution witness in alleged mob boss' trial, was found dead on a roadside.

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